Collection of Custom Configuration

Adding application configuration in app.config, especially under the appSetting key is something which every developer is used to.

 <appSettings>
<add key="Version" value="1.0" />
<add key="AutoSave" value="True" />
<add key="LoadOnWindowsStartUp" value="True" />
</appSettings>

What if we need to add our own customer collection. For example,

 <PluginSettings>
<Plugins>
<Plugin ID="906260f8-57ab-417a-8d83-015c73f4a5c8" IsEnabled="true"></Plugin>
<Plugin ID="906260f8-57ab-417a-8d83-015c73f4a5c9" IsEnabled="true"></Plugin>
</Plugins>
</PluginSettings>

That’s when we need to write up code to define these customized segments. We will begin with the basic element first, which in this case is

<Plugin ID="906260f8-57ab-417a-8d83-015c73f4a5c8" IsEnabled="true"></Plugin>

As seen, the basic element has two properties, a GUID named ID and a boolean value called IsEnabled. Let’s go ahead and define them. Our custom class needs to inherit from ConfigurationElement Class.

public class PluginConfigurationElement:ConfigurationElement
 {
 private const string XML_PLUGIN_ID = "ID";
 private const string XML_TITLE = "Title";
 private const string XML_IS_ENABLED = "IsEnabled";

[ConfigurationProperty(XML_PLUGIN_ID,IsRequired =true,IsKey =true)]
 public Guid ID
 {
 get
 {
 return (Guid)this[XML_PLUGIN_ID];
 }
 set
 {
 this[XML_PLUGIN_ID] = value;
 }
 }
 [ConfigurationProperty(XML_IS_ENABLED, IsRequired = true, DefaultValue =false)]
 public bool IsEnabled
 {
 get
 {
 return (bool)this[XML_IS_ENABLED];
 }
 set
 {
 this[XML_IS_ENABLED] = value;
 }
 }
 }

As seen in the example configuration, what we need is a collection of the defined Basic element. We will go ahead and define the collection now. Similar to basic element, we have a base class to inherit from.

public class PluginCollection:ConfigurationElementCollection
 {
internal const string PropertyName = "Plugin";

public override ConfigurationElementCollectionType CollectionType
 {
 get
 {
 return ConfigurationElementCollectionType.BasicMapAlternate;
 }
 }
 protected override string ElementName
 {
 get
 {
 return PropertyName;
 }
 }
 protected override bool IsElementName(string elementName)= elementName.Equals(PropertyName, StringComparison.InvariantCultureIgnoreCase);
 public override bool IsReadOnly() = false;
 protected override ConfigurationElement CreateNewElement()= new PluginConfigurationElement();
 protected override object GetElementKey(ConfigurationElement element) = ((PluginConfigurationElement)(element)).ID;
 protected override void BaseAdd(ConfigurationElement element) = base.BaseAdd((PluginConfigurationElement)element);

public void Add(PluginConfigurationElement element) = this.BaseAdd(element);
 public void Remove(Guid Key) = this.BaseRemove(Key);
 public void Clear() = this.BaseClear();

public PluginConfigurationElement this[int idx]
 {
 get
 {
 return (PluginConfigurationElement)BaseGet(idx);
 }
 }

 }

The final class we need to define is the actual Section itself.

public class PluginSection:ConfigurationSection
 {

 private const string XML_PLUGINS = "Plugins";

 [ConfigurationProperty(XML_PLUGINS)]
 public PluginCollection Plugins
 {
 get { return ((PluginCollection)(base[XML_PLUGINS])); }
 set { base[XML_PLUGINS] = value; }
 }
}

We are almost ready now. The final step required is to reference the class in app.config.

<configSections>
<section name="PluginSettings" type="MyNamespace.PluginSection, MyNamespace " />
</configSections>

Make sure you put this as the first step in app.config, right below the root element . Now you are all set to write your own configuration. Happy Coding.